Minerals

What is the difference in picture A and B? (Other than the obvious)

What is a mineral? Formed by natural processes such as cooling magma and evaporating saltwater Inorganic – not made by life processes Element or a compound with definite chemical composition (structure) Solid and crystalline (atoms in patterns that repeat over and over again)

S.N.I.F.C. Solid-not liquid, gas, or plasma Naturally Occurring-Not manmade Inorganic–Not alive, never was Fixed Composition - Same recipe everywhere, every time C rystalline Structure- shape of the mineral crystals

How are minerals classified? Minerals are grouped based on crystal systems. This means that they are classified according to their type of repeated crystal patterns.

How are minerals identified? (How can you tell them apart?) Color Hardness Luster Density Streak Breakage (Cleavage and Fracture) Unique properties

Color The same mineral can come in different colors. Color is not always a reliable way to identify a mineral due to factors such as: weathering and the inclusion of impurities-things that would cause the mineral to change color (air or water)

Hardness Hardness is determined by how easily a mineral can be scratched. Mohs Scale of Hardness is used to measure the hardness of a mineral

Hardness of Common Objects Mohs Scale Hardness Hardness of Common Objects Talc (softest) 1 Fingernail 2.5 Gypsum 2 Piece of copper 2.5-3.0 Calcite 3 Iron nail 4.5 Fluorite 4 Glass 5.5 Apatite 5 Steel file 6.5 Feldspar 6 Streak plate 7.0 Quartz 7 Flint sandpaper Topaz 8 Spinel (rock shops) Corundum 9 Emery sandpaper Diamond (hardest) 10 Carborundum sandpaper

Luster The way a mineral reflects light. Metallic, Nonmetallic, or submetallic

Density  

Streak The color of a mineral when it is in powdered form. Tested by streaking the mineral across streak plate (object must be harder than the mineral) Actual color of the mineral

Breakage Cleavage-tendency of some mineral to breaks along smooth, flat surfaces Fracture-tendency of some minerals to break with an uneven, rough, or jagged surface

Unique Properties Many minerals have unique characteristics that can also be used to identify the mineral. Example-natural magnet, double refraction, odor, taste, reaction to acids, fluorescence, etc.

Uses of Minerals Minerals are a component of everyday life because they are a part of everyday objects Jewerly (gems-rare minerals) Diamonds are used in industrial abrasives and cutting tools Some minerals are used to produce specific types of laser light Quartz is used in electronics Minerals that contain useful substances can be mined